This invention relates to a new and distinct variety of mushroom plant of Maitake mushroom, Grifola frondosa (Fr.) S. F. Gray. This new variety named ‘Grifon-7’ cultivated by repeated breeding of Maitake mushrooms having dominant traits, which has thick color of cap surface, white color of back side of cap, excellent cultivability and high yield and ensure presentable stability, reproducibility and uniformity.
Maitake has been artificially cultured and eaten in Japan since long time. The extract of Maitake obtained by hot water extraction contains ingredients that are effective in treatment of cancer because of which there is a great demand of it as a supplement. The demand of fresh Maitake is also increasing. In order to promote the sales of fresh Maitake, it is required that the variety can be cultured easily and the productivity improves. Good external appearance of mushroom, taste, storage characteristics are also important factors to make it appealing to consumers. Although Maitake has been cultured by isolating the strain from the wild variety, however, it has been unsuccessful to artificially control the culture environment that suits the culture of Maitake, because of which it could not be produced in a large scale. Consequently, a new variety called ‘Hokuto NT-100’, which is easy to culture and has improved quality, taste and storability, was developed as a result of repeated improvements through cross-breeding to improve the stability of culture and quality of mushrooms. This variety has been patented in US (U.S. Plant Pat. No. 17,984 P3). However, the under-face of the cap of the Hokuto NT-100 stained easily which made it look less fresh. Thus, the quality of its appearance was identified as a weakness. To overcome this weakness of Hokuto NT-100, cross-breeding was repeatedly conducted as a result of which a new variety named ‘Grifon120’ that has a white under-face of cap was developed and having U.S. Plant Pat. No. 21,575. However, it was pointed out that Grifon120 has thin color at the top surface of its cap, because of which it looked less fresh. Consequently, new varieties were developed, from which a new variety was selected and named as ‘Grifon-7’ after confirming its stability, reproducibility and uniformity.